What is the recommended antiretroviral treatment regimen for a 5-month pregnant woman with Human Immunodeficiency Virus (HIV)?

Antiretroviral Treatment for a 5-Month Pregnant Woman with HIV

Initiate or continue combination antiretroviral therapy (HAART) with a zidovudine (AZT) and lamivudine (3TC) backbone, combined with a third agent such as ritonavir-boosted lopinavir, darunavir, atazanavir, efavirenz, or raltegravir. 1, 2, 3

Treatment Approach Based on Clinical Scenario

If Already on HAART When Pregnancy Discovered

• Continue the current HAART regimen unless it contains teratogenic agents (efavirenz) or drugs with known adverse potential in pregnancy (stavudine + didanosine combination). 1, 3
• Do not stop antiretroviral drugs during pregnancy, even in the first trimester, if the woman requires treatment for her own health (CD4 <350 cells/mm³ or AIDS-defining illness). 1, 3
• Switch immediately from efavirenz to an alternative third agent due to documented neural tube defect risk. 1, 3
• Continue HAART throughout labor with intravenous zidovudine infusion during delivery. 1, 3

If Not Currently on HAART (Treatment-Naive)

For Women with HIV RNA >1000 copies/mL:

• Initiate HAART immediately (at 5 months gestation, first trimester concerns no longer apply). 1, 2, 3
• Use a zidovudine + lamivudine backbone combined with one of the following third agents: 1, 2
  • Ritonavir-boosted lopinavir (LPV/r)
  • Ritonavir-boosted darunavir (DRV/r)
  • Ritonavir-boosted atazanavir (ATZ/r)
  • Efavirenz (EFV) - acceptable at 5 months as neural tube closure is complete
  • Raltegravir (RAL)
• Continue through labor with IV zidovudine infusion. 1, 3
• Plan elective cesarean delivery at 38 weeks if viral load remains >1000 copies/mL at 34-36 weeks. 1, 3

For Women with HIV RNA <1000 copies/mL:

• Either initiate full HAART (preferred) or use zidovudine monotherapy antepartum with IV infusion during labor. 1
• HAART is increasingly preferred even in this scenario for maternal health and viral suppression. 3, 4

Critical Drug Selection Guidance

Strongly Recommended Backbone: Zidovudine + Lamivudine

The 2017 BMJ guidelines provide the most recent high-quality evidence and make a strong recommendation against tenofovir/emtricitabine/lopinavir-ritonavir due to increased risks of early neonatal death, preterm delivery, and stillbirth demonstrated in the PROMISE trial. 1, 2

• Zidovudine remains the cornerstone of perinatal HIV prevention and should be included whenever possible. 1, 2, 3, 5
• The BMJ guidelines suggest zidovudine/lamivudine-based regimens over tenofovir/emtricitabine-based regimens (weak recommendation for general comparison, strong recommendation against TDF/FTC/LPV/r specifically). 1, 2

Exceptions Where Tenofovir/Emtricitabine May Be Considered:

• Severe anemia (zidovudine causes hematologic toxicity) 1
• Lamivudine-resistant hepatitis B co-infection 1
• Documented zidovudine-resistant or lamivudine-resistant HIV 1
• Drug allergy to zidovudine or lamivudine 1
• Serious drug interactions with other medications 1

Drugs to Avoid:

• Efavirenz in first trimester (neural tube defects) - but acceptable at 5 months gestation 1, 3
• Stavudine + didanosine combination (lactic acidosis, hepatic steatosis) 1, 3
• Nevirapine in women with CD4 >250 cells/mm³ (severe hepatotoxicity risk) 1, 5

Monitoring Requirements

• Viral load assessment: At baseline, monthly initially, then at 34-36 weeks to guide delivery planning. 3
• CD4 count monitoring: To assess maternal immune status and need for opportunistic infection prophylaxis. 3
• Hematologic monitoring: Particularly for zidovudine-related anemia. 2, 3
• Medication adherence assessment at each prenatal visit. 2

Intrapartum Management

• Continue oral HAART throughout labor - do not interrupt the regimen. 1, 3
• Administer IV zidovudine during labor as continuous infusion, even if mother is on oral HAART. 1, 3, 5
• Offer scheduled cesarean section at 38 weeks if viral load >1000 copies/mL or unknown at 34-36 weeks (reduces transmission by approximately 50%). 1, 3, 5
• Vaginal delivery is reasonable if viral load <1000 copies/mL on HAART. 3

Infant Prophylaxis

• Administer zidovudine to newborn starting within 6-12 hours of birth at 4 mg/kg twice daily for 6 weeks. 1, 3, 5
• Obtain baseline complete blood count before starting and repeat after completing 6-week regimen. 3
• Breastfeeding is contraindicated in the United States to eliminate postnatal transmission risk. 3, 5, 6

Postpartum Maternal Management

• For women who started therapy solely for prevention (CD4 >350 cells/mm³, no AIDS-defining illness): May discontinue HAART after delivery if no indication for continued treatment. 1, 3
• For women requiring treatment for their own health: Continue HAART postpartum. 1, 3
• If discontinuing regimens containing drugs with long half-lives (NNRTIs), continue nucleoside analogues for 3-7 days after stopping the NNRTI to prevent resistance. 1, 3, 5

Common Pitfalls to Avoid

• Do not stop all antiretrovirals in the first trimester unless absolutely necessary, as this increases transmission risk and resistance development. 1, 3
• Do not use tenofovir/emtricitabine/lopinavir-ritonavir as this specific combination has the strongest evidence of harm. 1, 2
• Do not delay treatment initiation at 5 months gestation - the first trimester has passed and immediate viral suppression is critical. 2, 3, 4
• Ensure specialist involvement - HIV management in pregnancy is complex and requires experienced providers. 1, 3